Polyacrylamide Use in Reestablishing Arid Rangeland Species.

Polyacrylamide is a water absorbent material. The purpose of this study was to evaluate polyacrylamide’s effects on Crested Wheatgrass (Agropyron cristatum (L.) Gaertn.), Yellow Sweet Clover, Sagebrush (Artemisia tridentata (Nutt.) wyomingensis Beetle & Young), Forage Kochia (Bassia scoparia (L.) A.J.Scott), Lewis Flax (Linum lewisii Pursh), and Bottlebrush Squirreltail (Elymus elymoides(Raf.) Swezey) germination and seedling longevity grown under glasshouse conditions. Approximately 8 kg of Tooele loam was added to 30 cm square boxes. The soil was formed to simulate a furrow system with the seeds in the furrow bottom. Polyacrylamide was applied at 1519 and 3039 kg ha^-1 in a band 8 cm below the surface of the furrow. The soil was saturated initially and no more water was added throughout the study. Seeds were planted immediately after saturation. Germination and seedling vigor were monitored from planting until death of all emerged plants. Daily soil moisture was recorded at the top of the ridge, on the slope, and in the furrow. At twenty-one days after planting, soil moisture near the low and high PAM rates were over two and eight times greater than the control, respectively. There was no difference in germination, but seedling longevity in Crested Wheatgrass, Yellow Sweet Clover, Lewis Flax, and Forage Kochia were all greater than the control. At the high rate of polyacrylamide, Forage Kochia seedlings survived for 49 days in contrast to the control seedlings surviving for 28 days. PAM application has shown to prolong soil moisture and seedling survival in this study though the seedlings that survived the longest were nearest to the PAM band. Further research must be conducted to understand the properties of PAM once dried in the soil, proper application depths, influences on the native environment, the time period that PAM retains soil moisture and its influence on plant health.